Brett Kavanaugh’s confirmation hearings dragged on endlessly today, and aside from a few exciting outbursts from protestors, not much happened. But an exchange between Senator Kamala Harris and Kavanaugh brought some real tension to the proceedings.

Harris seemed to imply she knew about a conversation Kavanaugh had with someone working at Trump’s law firm about the Mueller Probe. Kavanaugh appeared caught off guard by the question, and tried to weasel his way out of replying before Senator Mike Lee interrupted with an objection. “This town is full of law firms, law firms are full of people, law firms have a lot of names, there are a lot of people who work at a lot of law firms,” Lee said, helpfully, before a protestor yelled from the back of the room, in turn interrupting him.

But what was this question about? Harris seemed to be aware of a specific incident but was not willing to name the person or conversation she was referring to, preferring to press Kavanaugh on his memory of the alleged event. “Be sure about your answer, sir,” she said in a vaguely menacing tone.

Kavanaugh eventually said he would need a roster of employees at the law firm Kasowitz, Benson & Torres and more information if he was to answer the question, and Harris moved on.